Cucos, formigas, abelhas e a evolução dos instintos

Abstract

In this paper, I examine Chapter VII of "The Origin of Species" (Instinct), in which Charles Darwin applies evolutionary theory by natural selection to the instinct domain and lays the foundations of a biological analysis of behavior. Darwin intended to show the possibility of gradual evolution in the case of complex behaviors such as brood parasitism in cuckoos, slave-making habits in ants and geometrical cell building in honey bees. Darwin attributed functional value to behavioral characters, used the comparision of related species' behavior as a way to infer evolutionary stages, gave cost-and-benefit and optimization processes a role as selection criteria, took into account aspects of behavioral competition and manipulation and gave a group selection approach to the question of sterile castes of eusocial insects. More than results and solutions, Darwin offered, in his chapter about Instinct, a paradigm for the analysis of species typical behaviors, a true starting point for modern approaches such as ethology and behavioral ecology.